A PDMS-Based Integrated Stretchable Microelectrode Array (isMEA) for Neural and Muscular Surface Interfacing

• Published in: IEEE transactions on biomedical circuits and systems Vol. 7; no. 1; pp. 1 - 10
• Main Authors: Liang Guo, Guvanasen, G. S., Xi Liu, Tuthill, C., Nichols, T. R., DeWeerth, S. P.
• Format: Journal Article
• Language: English
• Published: United States IEEE 01.02.2013; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Animals; Cells, Cultured; Compliant; Dimethylpolysiloxanes; Electrodes; epimysial; Fabrication; Gold; integrated packaging; Materials Testing; Mice; microelectrode array (MEA); Microelectrodes; microfabrication; Muscle Fibers, Skeletal - cytology; Muscle Fibers, Skeletal - metabolism; Muscles; Neural Prostheses; neural prosthesis; neural recording and stimulation; Neurons - cytology; Neurons - metabolism; Nylons; polydimethylsiloxane (PDMS); Printed circuit boards; Rats; stretchable; Substrates; surface; Surface impedance; Surface treatment
• ISSN: 1932-4545; 1940-9990
• DOI: 10.1109/TBCAS.2012.2192932

Numerous applications in neuroscience research and neural prosthetics, such as electrocorticogram (ECoG) recording and retinal prosthesis, involve electrical interactions with soft excitable tissues using a surface recording and/or stimulation approach. These applications require an interface that is capable of setting up high-throughput communications between the electrical circuit and the excitable tissue and that can dynamically conform to the shape of the soft tissue. Being a compliant material with mechanical impedance close to that of soft tissues, polydimethylsiloxane (PDMS) offers excellent potential as a substrate material for such neural interfaces. This paper describes an integrated technology for fabrication of PDMS-based stretchable microelectrode arrays (MEAs). Specifically, as an integral part of the fabrication process, a stretchable MEA is directly fabricated with a rigid substrate, such as a thin printed circuit board (PCB), through an innovative bonding technology-via-bonding-for integrated packaging. This integrated strategy overcomes the conventional challenge of high-density packaging for this type of stretchable electronics. Combined with a high-density interconnect technology developed previously, this stretchable MEA technology facilitates a high-resolution, high-density integrated system solution for neural and muscular surface interfacing. In this paper, this PDMS-based integrated stretchable MEA (isMEA) technology is demonstrated by an example design that packages a stretchable MEA with a small PCB. The resulting isMEA is assessed for its biocompatibility, surface conformability, electrode impedance spectrum, and capability to record muscle fiber activity when applied epimysially.